A manufacturing method of a semiconductor device in which the oxygen and carbon concentrations are reduced at the interface of each layer making up the semiconductor multilayer film. A first semiconductor layer is formed on a single-crystal substrate in a first reactor; the substrate is transferred from the first reactor to a second reactor through a transfer chamber; and a second semiconductor layer is formed on the first semiconductor layer in the second reactor. During substrate transfer, hydrogen is supplied when the number of hydrogen atoms bonding with the surface atoms of the first semiconductor layer is less than the number of surface atoms of the first semiconductor layer, and the supply of hydrogen is stopped when the number of hydrogen atoms bonding with the surface atoms of the first semiconductor layer is greater than the number of surface atoms of the first semiconductor layer.